The present invention relates to a method and an apparatus for picking up a semiconductor chip and a suction and exfoliation tool for picking up a semiconductor chip which is cut out from a wafer and adhered to an adhesive sheet.
Semiconductor chips have been made thinner due to the recent miniaturization of electronic parts, and semiconductor chips with quite small thickness of 100 μm or less have been put to practical use. However, since such semiconductor chips thus thinned are apt to be broken quite easily, it is difficult to handle the semiconductor chips. In particular, it is quite difficult to take out respective pieces of semiconductor chips cut out from a wafer. In this taking-out procedure, such a procedure is repeatedly performed that the semiconductor chips adhered to an adhesive sheet are exfoliated one by one from the sheet and picked up by a suction nozzle. However, when the conventionally employed semiconductor chip exfoliating method, that is, the method of raising the semiconductor chips by a needle from the lower part of the sheet is employed, there arises a problem that breakage or crack etc. may appear frequently at the semiconductor chips.
In order to eliminate such a problem, recently there has been employed a method that the sheet is exfoliated from the lower surfaces of the semiconductor chips by vacuum suction force when taking out the semiconductor chips from the sheet. According to this method, since it is not necessary to raise the semiconductor chips by the needle, it is possible to prevent the problem such as breakage or chip of the semiconductor chips from occurring. Such technique is disclosed, for example, in JP-A-2001-118862.
However, according to the aforesaid method, it is difficult to exfoliate the sheet from the semiconductor chips merely by vacuum-sucking the sheet from the lower surface thereof, so that an auxiliary means for accelerating the exfoliating process of the sheet is required to be employed jointly. For example, such an exfoliation acceleration process is required to be employed jointly that the vacuum sucking surface is moved relatively on the lower surface of the sheet along the lower surface to lower an adhesive force between the sheet and the chip. To this end, it is required to control a mechanical system in a complicated manner, and further a tact time is required due to the repetition of a complicated operation at every picking-up operation thereby to cause a delay time, so that it is impossible to realize a high productivity.